1. Use IUPAC temporary systematic naming rules for undiscovered elements.

2. For atomic number $119$, write the digits separately: $1,\;1,\;9$

3. Replace each digit by its IUPAC root:

   • $1 \to \text{un}$
   • $1 \to \text{un}$
   • $9 \to \text{enn}$

4. Combine the roots and add the ending "$ium$": $\text{un} + \text{un} + \text{enn} + \text{ium} = \text{ununennium}$

5. The symbol is formed from the first letters of the roots: $\text{un} \to u,\quad \text{un} \to u,\quad \text{enn} \to e$ So the symbol is: $\boxed{\text{Uue}}$

6. Comparing with the options:

   • A: $\text{uun}$ ❌
   • B: $\text{une}$ ❌
   • C: $\text{uue}$ ✅
   • D: $\text{unh}$ ❌

Therefore, the correct option is C.